The present disclosure relates to an air conditioner including a pipe configured to attenuate vibration generated in a refrigeration cycle.
An air conditioner refers to an apparatus that cools or heats an indoor space by using a refrigeration cycle. The refrigeration cycle includes a compressor, a condenser, an expansion device, and an evaporator, and the compressor, the condenser, the expansion device, and the evaporator are sequentially connected by pipes. A refrigerant circulates the compressor, the condenser, the expansion device, and the evaporator through the pipes.
A flow path is formed in the condenser and the evaporator in the refrigeration cycle. The refrigerant is heat-exchanged with surroundings while passing through the flow path formed in the condenser and the evaporator to be condensed or evaporated, and the condenser and the evaporator serve as a heat exchanger. The flow path is used to allow the refrigerant to flow therethrough, and the refrigerant flows in the flow path. Hence, the flow path is a concept included in the pipe in a broad sense.
Such a pipe connects components of the refrigeration cycle to each other, and is used as a flow path of the compressor and the condenser. The conventional pipe is mainly made of a copper (Cu) material. However, pipes made of copper have a few problems.
First, the copper has a limitation in reliability due to occurrence of corrosion. In the case of a chiller heat transfer pipe, the chiller heat transfer pipe is cleaned or replaced to remove scales, etc. therein.
Next, the copper does not sufficiently have a high pressure resistance property when it is used for a flow path of a new high-pressure refrigerant such as R32. If a pipe made of the copper is used as a flow path of a new high-pressure refrigerant, the pipe does not endure high pressure as time elapses and therefore may be damaged.
In order to solve problems of such copper pipes, Korean Patent Laid-Open Publication No. 2003-0074232 has disclosed a stainless steel pipe. The stainless steel pipe is made of a stainless steel material, and the stainless steel material generally has a strong corrosion resistance as compared with the copper material. Thus, the stainless steel tube can solve the problem of the copper pipes, i.e., the occurrence of corrosion. In addition, the stainless steel material has a sufficient high pressure resistance property, and hence it is less likely that the stainless steel material will be damaged even at high pressure.
However, the conventional stainless steel material including the stainless steel pipe disclosed in Korean Patent Laid-Open Publication No. 2003-0074232 has properties of excessively high strength and hardness as compared with the copper material, and therefore, there occurs a problem of processability, which does not occurs in the copper pipes.
The pipe used in the air conditioner may be formed in not only a linear shape but also curved shape due to spatial constraints. One portion of the pipe may be formed in a linear shape, and another portion of the pipe may be formed in a curved shape. A linear pipe refers to a pipe extending in one direction along a straight line, and a curved pipe refers to a pipe curved along a curve.
However, since the conventional stainless steel material has properties of excessively high strength and hardness as compared with the copper material, it is very difficult to manufacture a curved pipe using the stainless steel material (see FIG. 1). For example, although a linear pipe made of the stainless steel material is processed as a curved pipe by mechanically applying a force to the linear pipe, the linear pipe is not completely plastically deformed but partially plastically deformed. Therefore, sufficient processing is not performed.
In particular, it is known that the stainless steel material essentially has properties of high strength and high hardness. Therefore, it is recognized that it is difficult to improve the processability of the stainless steel material as long as the stainless steel material is used.
Moreover, since the pipe occupies 10% or more of the total material cost of the air conditioner, a demand for improving the performance of the pipe and reducing the cost of the pipe is continuously increasing.
Meanwhile, the compressor is configured to compress the refrigerant, and vibration is generated from the compressor in a process of compressing the refrigerant. The vibration generated from the compressor are transferred to another component of the refrigeration cycle along the pipe, which causes noise, and becomes the cause that decreases the durability of the air conditioner from a long-term point of view. In addition, the vibration and noise cause a pressure drop of the refrigerant passing through the pipe, and hence the efficiency of the refrigeration cycle is deteriorated.
Conventionally, there was a case where a flexible pipe is applied so as to solve such a problem. The flexible pipe refers to a pipe having a structure in which the outer circumferential surface of the flexible pipe is surrounded by a wire braid.
If the flexible pipe is applied to the refrigeration cycle, vibration can be attenuated to a certain degree. However, the flexible pipe does not have sufficient durability due to local cohesiveness. In addition, a pressure drop occurs in the refrigerant passing through the flexible pipe, and therefore, the efficiency of the refrigeration cycle is deteriorated.
Accordingly, the introduction of a new pipe for solving the conventional problems is required.